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In this paper, a CFD analysis of airflow and contaminant distribution within enclosed vehicular parking facilities is presented. First, the CFD simulation is validated using field data. Then, the results of a parametric CFD analysis are summarized. In particular, it was found that significant fan
energy savings can be obtained when simple on-off controls are properly implemented without affecting the indoor air quality within the garage. Moreover, it was found that the position

Today the use of energy efficient technology and renewable energy sources have not become mainstream in the building industry. One of the main reasons for this is thought to be that each part in the building is considered separately. The approach in the newly started EU-project, IDEEB, is to adopt comprehensive view. This considers the building itself and its installations as one energy system to achieve the required indoor comfort at the same time as reducing environmental impact.

The mixing of different air streams is a process commonly found in air handling systems. One of the most common examples of this process is found in the air handling unit mixing box where outdoor air is mixed with return air. In the adiabatic mixing process, the energy leaving the mixing box equals the energy entering the mixing box. In order to calculate the energy in the mixed air stream, it is only necessary to know the energy in the outdoor and the return air streams. As a result, it is not necessary to consider whether the mixing process is ideal or not.

DEVELOPMENT OF A PCM AIR FILTER AND ITS APPLICATION TO A CONSTANT The authors have developed a PCM air filter which stabilizes the temperature of air passing though it. This PCM filter has great potential for applications that require a constant temperature air supply. In addition, it can simplify temperature control systems and can contribute to energy conservation. The material in the filter consists of sponge fibers coated with paraffin followed by a coating of resin to prevent leakage and vaporization of the paraffin.

In summer, most areas in Japan are hot and humid. Hokkaido Island, which is the most northern part of Japan, is the only exception. However, air conditioning systems have become the norm in all big buildings in Japan, even in Hokkaido, due to increased internal generation of heat from lights and equipment such as computers and printers. However, the outside air temperature often drops below 26C during summer everywhere in Japan even when cooling and air conditioning is turned on.

The authors have proposed a system for stabilizing air temperature using direct heat exchange between granulated phase change materials (PCM) and air. This paper describes experiments in which air whose temperature is periodically changed to simulate changes of outdoor air temperature is passed through a bed of granulated PCM. These experiments demonstrate that output air temperature is stabilized and remains within the phase change temperature range. Results calculated by a computer simulation program described in a previous paper duplicate the experimental results.

Using performance characteristics of balanced ventilation units tested in laboratory of CETIAT, a complete ventilation system in an individual house is modelised, in details. Simulations are made with TRNSYS program and hourly dynamic calculations on the heating season, on different French climates (three) and different ventilation configurations (five) : high efficiency or classical balanced system inside the attic or inside the heated volume and simple exhaust ventilation system.

The CEN TC 156 / WG2 (ventilation for residential buildings) has prepared a new European draft for the test method of Heat Recovery Units (prEN 13141-7). This method should ensure a common way of testing these units all over Europe. In order to determine if the draft procedure is sufficient enough, both VTT and CETIAT has proceeded to some tests according to the new European standard on the same unit. Results on this first intercomparison give interesting data on the test method applied.

In low energy dwellings the ventilation heat losses are significant. Reduction of these heat losses can be achieved by introducing demand controlled ventilation i.e. ventilation rates are set below normal level when rooms are no longer occupied. This paper outlines preliminary results on energy conservation and health effects in relation to demand controlled ventilation in a low-energy house.

This paper shows that it is possible to calculate the optimal outdoor air rate at different outdoor temperatures in the economiser cycle. The price of heat must increase 3 times before the optimal outdoor air rate during heating gets lower than during cooling. The optimal outdoor air rate during heating is determined primarily by the price of heat. The optimal outdoor air rate during cooling is determined primarily by the price of cooling capacity.